Aston Villa goalkeeper and U.S. international Brad Guzan believes the young defense in front of him at the Premier League club will improve thanks to their tough go last season.

Villa finished 15th last season and needed a few good results down the stretch to avoid feeling the head of relegation.

“We had a tough spell but that was what made us stronger and helped to bring out our character” Guzan told the Birmingham Mail. “When you go through those tough times you are able to help each other, pick each other up and dust each other down. You keep fighting.”

The defense at Villa Park allowed 68 goals throughout the league season, tied for the second-most in the Premier League.

“If you make mistakes it’s how you respond to the criticism that comes your way, you have to be man enough and move on. I think as a group and as a team we did a really good job of that and that will help us now in the future.”

It will be an important and crucial season for the young defensive unit. Captain Ron Vlaar and right-back Alan Hutton are 28 years old, but aside from those two not a single defender on the Villa roster is older than 24. Hutton probably won’t even be back next season as he looks to renew his loan spell with Real Mallorca, leaving Guzan and Vlaar to guide the roster into next season.

Vlaar saw both 23-year-old Ciaran Clark and 22-year-old Nathan Baker split time next to him in central defense, although Clark was dropped from the lineup down the stretch.

23-year-old Joe Bennett received most of the playing time down the left-hand side from manager Paul Lambert last year, and 24-year-old Matthew Lowton impressed on the right.

Guzan praised the young group’s effort, and pointed out how much of a trial-by-fire it really was.

“You need the help of defenders, and you need them to be brave because in England there are lots of balls coming into the box” said the 28-year-old keeper. “I think they improved massively. The guys in front of me did a really good job coming into a situation that maybe wasn’t the easiest. For them to learn as they went along – some new guys, some younger faces that have learnt on the job – was a tough ask. But they just got on with it, and that’s a test of their mental strength and focus.”

Villa have added two more youngsters to the defensive unit this summer, and they will be given a full preseason to prepare with Guzan and the rest of the squad. 20-year-old Jores Okore joined Lambert’s men from FC Nordsjaelland in Denmark for just over £4 million ($6 million), and 22-year-old Antonio Luna came over from Spain’s Sevilla.